The present invention relates to a sound field controller for intensifying impression of a sound field such as reverberation and spatial impressions and for realizing natural sounds with simple constitution.
In conventional electronic musical instruments, a waveform of music sound is generated by a tone generating circuit or a tone generator. An effect for example, echo, reverberation, or tremolo is appropriately imparted to the generated music sound. The resultant music sound is amplified by a power amplifier, and the amplified music sound is emitted to a surrounding space through a single loudspeaker or a plurality of loudspeakers.
In the conventional electronic musical instrument, the effects except for tremolo caused by loudspeaker rotation are normally imparted by electrical signal processing, which could not create natural sound field effects such as echo and reverberation. In addition, sound effects are separately imparted for different musical instruments. In ensemble, the quality, volume, length and so on of acoustics such as reverberation differ from one instrument to another, thereby sometimes losing integrity of performance or causing a sense of incongruity.
Aside from above, an acoustic feedback system is known as a sound field support apparatus for intensifying the reverberation and spatial impressions in a listening room. In this conventional system, a loudspeaker and a microphone are separately arranged in a room by an appropriate distance. A sound picked up by the microphone is supplied to a FIR (Finite Impulse Response: non-cyclic) filter through a head amplifier to generate a reverberation signal (mainly an initial reflection signal). The generated reverberation signal is reproduced from the loudspeaker through a power amplifier. The reproduced sound is picked up by the microphone. This loop is repeated to increase the impression of volume (or increase sound pressure), to increase the impression of reverberation (or extend reverberation time). and to increase the impression of space (or intensify a side reflection tone energy).
However, imparting of reverberation by the sound field support system requires the dedicated loudspeakers. This system also requires one to install the microphones and the loudspeakers on the walls and ceiling of the room, to arrange a main frame of the apparatus independently or separately from the microphones and the loudspeakers, and to wire signal cables on the walls and ceiling of the room, thereby making the scale of the system large and therefore making the installation of the system difficult.